[Current achievements and future perspectives in the research on intravascular large B-cell lymphoma]

Intravascular large B-cell lymphoma is a rare disease entity of extranodal large B-cell lymphoma and is characterized by selective growth of tumor cells in the lumina of small vessels in systemic organs. The challenge in obtaining sufficient tumor cells from biopsy specimens has hampered the elucidation of underlying biology. Recent advances in xenograft models and plasma cell-free DNA have revealed that the intravascular large B-cell lymphoma has genetic features similar to those of activated B-cell-like diffuse large B-cell lymphoma and frequent genetic alterations in immune-check point related genes. In terms of clinical aspects, considering the improvement in the clinical outcomes and higher risk of secondary central nervous system (CNS) involvement in the rituximab era, phase 2 trial of R-CHOP therapy combined with high-dose methotrexate and intrathecal chemotherapy as CNS-oriented therapy was conducted. The trial, named the PRIMEUR-IVL study, displayed good progression-free survival and low cumulative incidence of secondary CNS involvement. Further research is necessary to enable a deeper understanding of the pathophysiology of the disease and further improve the clinical outcomes.